About this replacement
Ecovacs Winbot Mini / W1S / W2 Pro — 3.7V Li-ion Replacement Battery (201-2432-0438)
This is a 3.7V 2600mAh Li-ion battery for the Ecovacs Winbot Mini, Winbot W1S, and Winbot W2 Pro window cleaning robots. It slots in place of OEM part 201-2432-0438 (also cross-referenced as S32-LI-36-3000). Replace it when the original no longer holds a charge or the robot loses suction partway through a cleaning cycle.
- Winbot Mini, W1S, and W2 Pro compatibility: All three models run the same 3.7V cell platform with a shared connector format and BMS handshake protocol. The battery management system across this series monitors cell voltage and current draw from the same baseline, so one cell covers all three without modification.
- Bench tested on actual hardware: We ran this cell through full charge and discharge cycles on a Winbot Mini and monitored the BMS response under sustained motor load. The protection circuit tripped correctly at low-voltage cutoff and recovered cleanly on reconnect to the charger.
- Post-cleaning storage tip for window robots: The Winbot series parks in a vertical cradle between uses. If the robot sits docked for weeks between cleans, charge it fully before storage and disconnect it from the cradle — extended cradle connection without active charging accelerates cell degradation in small-capacity Li-ion packs like this one.
Why the Winbot cuts suction before the battery indicator drops
The Winbot's suction pad relies on consistent motor voltage to maintain the vacuum seal against the glass. As the cell ages and internal resistance rises, voltage sags under motor load even when the reported charge level still reads mid-range. The robot's BMS reads terminal voltage, not state-of-charge directly, so the indicator can show 50% while the actual voltage under load has already fallen below the motor's minimum operating threshold. Replacing the cell restores full voltage delivery under load and brings the suction pad back to spec.
Robot stops mid-clean and then restarts after a few seconds
This stop-restart pattern is a BMS overcurrent trip, not a motor fault. It happens when the cleaning pad or suction port is partially blocked, forcing the motor to draw more current than the protection circuit allows. The BMS cuts output, the motor cools briefly, and the circuit resets. Check the suction port and pad seal for debris before swapping the battery — if the port is clear and the behaviour continues, the existing cell's protection circuit is tripping at a degraded current threshold, and replacement will resolve it. After fitting the new cell, verify the robot completes a full uninterrupted pass at 3.7V nominal.